diff mbox series

[v3,8/8] Documentations: probes: Update fprobe document to use ftrace_regs

Message ID 169181869006.505132.4695602314698748304.stgit@devnote2
State New
Headers
Series bpf: fprobe: rethook: Use ftrace_regs instead of pt_regs |

Commit Message

Masami Hiramatsu (Google) Aug. 12, 2023, 5:38 a.m. UTC 
  From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Update fprobe document so that the entry/exit handler uses ftrace_regs
instead of pt_regs.

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 Documentation/trace/fprobe.rst |   14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/Documentation/trace/fprobe.rst b/Documentation/trace/fprobe.rst
index a6d682478147..8eee88eda4e6 100644
--- a/Documentation/trace/fprobe.rst
+++ b/Documentation/trace/fprobe.rst
@@ -91,9 +91,9 @@  The prototype of the entry/exit callback function are as follows:
 
 .. code-block:: c
 
- int entry_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct pt_regs *regs, void *entry_data);
+ int entry_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data);
 
- void exit_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct pt_regs *regs, void *entry_data);
+ void exit_callback(struct fprobe *fp, unsigned long entry_ip, unsigned long ret_ip, struct ftrace_regs *fregs, void *entry_data);
 
 Note that the @entry_ip is saved at function entry and passed to exit handler.
 If the entry callback function returns !0, the corresponding exit callback will be cancelled.
@@ -112,12 +112,10 @@  If the entry callback function returns !0, the corresponding exit callback will
         This is the return address of the traced function. This can be used
         at both entry and exit.
 
-@regs
-        This is the `pt_regs` data structure at the entry and exit. Note that
-        the instruction pointer of @regs may be different from the @entry_ip
-        in the entry_handler. If you need traced instruction pointer, you need
-        to use @entry_ip. On the other hand, in the exit_handler, the instruction
-        pointer of @regs is set to the currect return address.
+@fregs
+        This is the `ftrace_regs` data structure at the entry and exit. Note that
+        the instruction pointer of @fregs may be incorrect in entry handler and
+        exit handler, so you have to use @entry_ip and @ret_ip instead.
 
 @entry_data
         This is a local storage to share the data between entry and exit handlers.